Tool for installation and removal of retention knobs

ABSTRACT

A retention knob tool. A tubular body, is held in the tubular sleeve, and symmetrically formed around an axis. The tubular body also has an internal bore. Four locking ball retainer sockets are formed in the tubular body. A retention knob aperture is recessed within a top plate. Four balls are movably held in the ball retainer sockets. A tubular end stop is affixed to the tubular body rearward end. A drive tool cavity is recessed within the tubular body rearward end. The sleeve forward end includes a recessed circumferential portion bounded by a first thicker portion of the inside wall, where the first thicker portion bears against the balls when the tubular body is translated rearwardly into an inward lock position and the inward force is removed from the plurality of balls when the tubular body is extended forwardly into a release position.

TECHNICAL FIELD

The present invention relates to a tool for installation and removal ofretention knobs used in CNC tooling machines in general, and, moreparticularly, a tool for installation and removal of retention knobshaving a set of balls within a dual mode socket tool arranged to capturea retention knob.

BACKGROUND

The present disclosure provides new and novel solutions to overcomeproblems inherent in the art of Computer Numerical Control (CNC)machining. CNC refers to the automated control of machining tools likedrills, boring tools, and lathes by a computer. Using, various types ofsuch tools, a CNC machine alters a blank piece of material (metal,plastic, wood, ceramic, or composite) to meet precise specifications byfollowing programmed instructions and without a manual operator.Different tools are held by a tool holder and changed by an operator asneeded for various machining functions.

A small engagement facilitating device, known as a retaining knob (alsosometimes called a pull stud), includes a threaded shank that rotatablysecures into the threaded aperture of a tool holder in a CNC machine. Inaddition to the threaded shank section, retaining knobs are configuredto further include an enlarged diameter section, relatively thin flangesection, and an elongated neck section that extends upward from theflange to a knob section at the distal end of the retaining knob.Parallel wrenching flats are milled or otherwise formed at diametricallyopposite sides of the flange section.

Typically, a CNC machine includes an engagement tip which securely gripsthe knob section, elongated neck, and flange sections of a retainingknob in order to mount to a tool holder. Due to the high amount oftorque that is transmitted through a retaining knob from the spindle ofa CNC machine, to the tool holder and attached tool, the threaded shanksection of a retaining knob must be rotatably secured in the threadedaperture of the tool holder at a high degree of torque (on the order of85 ft. lbs.). This torque is applied to the retaining knob at therelatively thin wrenching flats of the flange section of a retainingknob. Substantially, the entire remainder of the retaining knob outersurface is circular in configuration. Thus, the relatively thinwrenching flats provide the only obvious gripping surface for use increating a rotational force to remove and install a retaining knob froma tool holder.

Often an open-ended wrench is used for removal of a retaining knob.However, this has the disadvantage of rounding the flat surfaces of theretaining knob over time causing damage to the retaining knob andshortening its useful life. Another disadvantage is that use of a wrenchcan cause injury to an operator since the wrench can easily slip off ofthe wrenching flats. Further, use of a crescent wrench or the like,requires a two-step operation of loosening the retaining knob with thewrench, followed by actual removal of the retaining knob using anoperator's fingers to prevent the knob from falling.

One type of a pull stud removal device was disclosed in U.S. Pat. No.6,360,634B1 issued Mar. 26, 2002 to Leitch. Unfortunately, this devicewas rather cumbersome to use as it required attaching and removing thedevice on to and from a retaining knob using a sideways motion requiringa precise alignment of the tool to the retaining knob.

Thus there is a continuing need in the art for a tool that can securelyattach and facilitate removal of a retaining knob from a CNC toolholder, while limiting damage to the retaining knob.

BRIEF SUMMARY OF THE DISCLOSURE

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This summary is not intended to identify key features ofthe claimed subject matter, nor is it intended to be used as an aid indetermining the scope of the claimed subject matter.

A tool for installation and removal of retention knobs is providedincluding a tubular sleeve with an inside tubular wall, a sleeve forwardend and a sleeve rearward end. A tubular body, is slidingly held in thetubular sleeve, the tubular body being symmetrically formed around anaxis and including a forward end and a rearward end. The tubular bodyalso has an internal bore bounded by an internal tubular wall surfaceand a rearward wall, and an external tubular body surface, wherein theforward end is joined with a top plate having a larger diameter than thetubular body surface. At least two locking ball retainer sockets areformed in the tubular body at the forward end rearwardly from the topplate. The retainer sockets are substantially normal to the axis andlocated radially uniformly around the tubular body. A retention knobaperture is recessed within the top plate. A plurality of balls ismovably held in the ball retainer sockets. A tubular end stop is affixedto the tubular body rearward end, where the tubular end stop is insertedinto the tubular sleeve, where the tubular sleeve further includes aprotruding circumferential edge sized to strike against the tubular endstop when the tubular body is translated into a release position. Adrive tool cavity is recessed within the tubular body rearward end,where the drive tool cavity is sized and configured for receival of adrive tool. The sleeve forward end includes a recessed circumferentialportion bounded by a first thicker portion of the inside wall, where thefirst thicker portion bears against the plurality of balls forcing theplurality of balls inwardly when the tubular body is translatedrearwardly into an inward lock position and the inward force is removedfrom the plurality of balls when the tubular body is extended forwardlyinto a release position.

BRIEF DESCRIPTION OF THE DRAWINGS

While the novel features of the invention are set forth withparticularity in the appended claims, the invention, both as toorganization and content, will be better understood and appreciated,along with other objects and features thereof, from the followingdetailed description taken in conjunction with the drawings, in which:

FIG. 1 schematically shows a prospective exploded view of an example ofa retaining knob tool for removal and attachment of a retaining knob.

FIG. 2A schematically shows a planar cross-section of the tool of FIG. 1in a release position.

FIG. 2B schematically shows a planar cross-section of the tool of FIG. 1in an inward lock position.

FIG. 3 schematically shows an example of a tubular body including aninternal bore used in the retaining knob tool.

FIG. 4 schematically shows an example of a stop for limitinglongitudinal travel of the tubular body.

FIG. 5 schematically shows an example of a tubular sleeve as used in theretaining knob tool as seen from a sleeve rearward end.

FIG. 6 shows an illustration of an assembled retaining knob tool in aretaining knob release position.

FIG. 7 shows an example of an assembled retaining knob tool in aretaining knob inward lock position.

In the drawings, identical reference numbers identify similar elementsor components. The sizes and relative positions of elements in thedrawings are not necessarily drawn to scale. For example, the shapes ofvarious elements and angles are not drawn to scale, and some of theseelements are arbitrarily enlarged and positioned to improve drawinglegibility. Further, the particular shapes of the elements as drawn, arenot intended to convey any information regarding the actual shape of theparticular elements, and have been solely selected for ease ofrecognition in the drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following disclosure describes several examples of a retaining knobtool used for installing and removing a CNC type retaining knob. Severalfeatures and elements in accordance with example embodiments are setforth and described in the Figures. It will be appreciated thatalternatives in accordance with other example embodiments can includeadditional elements or features different than those shown in theFigures. Example embodiments are described herein with respect to aretaining knob tool using a mating drive socket device. However, it willbe understood that these examples are for the purpose of illustratingthe principles, and that the invention is not so limited. Additionally,methods and systems in accordance with several example embodiments maynot include all of the features shown in the Figures.

Unless the context requires otherwise, throughout the specification andclaims which follow, the word “comprise” and variations thereof, suchas, “comprises” and “comprising” are to be construed in an open,inclusive sense that is as “including, but not limited to.”

Reference throughout this specification to “one example” or “an exampleembodiment,” “one embodiment,” “an embodiment” or various combinationsof these terms means that a particular feature, structure orcharacteristic described in connection with the embodiment is includedin at least one embodiment of the present disclosure. Thus, theappearances of the phrases “in one example” or “in an example” invarious places throughout this specification are not necessarily allreferring to the same example or embodiment. Furthermore, the particularfeatures, structures, or characteristics may be combined in any suitablemanner in one or more embodiments.

Referring now to FIG. 1, a prospective exploded view of an example of aretaining knob tool for removal and attachment of a retaining knob isschematically shown. A typical retention knob 34 includes a knob section60 adjoined to an elongated neck 62 further adjoined to flange sections64 and having a threaded shank section 66 for threading into a CNCtoolholder 67. A retention knob tool 10 for installation and removal ofa retention knob 34 includes a tubular body 12 symmetrically formedaround an axis 18 and including a forward end 14 and a rearward end 16.The tubular body 12 includes an internal bore 20 defined by an internaltubular wall surface 22 and a rearward wall 24 (elements 20, 22 and 24are best shown below in FIG. 2A), and an external tubular body surface26, wherein the forward end 14 is joined with a top plate 28 having alarger diameter than the tubular body surface 26. At least two lockingball retainer sockets 30 are formed in the tubular body 12 at theforward end 14 below the top plate 28. The retainer sockets 30 aresubstantially normal to the axis 18 and located radially uniformlyaround the tubular body 12.

A plurality of balls 32 are sized to fit into the ball retainer sockets30 and are moveable therein between a release position (as best shown,for example, in FIG. 2A) and an inward lock position (as best shown, forexample, in FIG. 2B). In one useful example, four balls may beindividually inserted into one of four sockets that are substantiallyuniformly positioned around the circumference of the tubular body 12.Each socket, therefore, holds a single ball. A drive tool cavity 36, isrecessed within the tubular body rearward end 16. The drive tool cavity36 is sized and configured for receival of a drive tool 72 to which thedevice attaches. A tubular sleeve 42 with an inside tubular wall 44 issized to slidingly receive a portion of the tubular body between the topplate 28 and the rearward end 16, where the tubular sleeve 42 includes asleeve forward end 46 and a sleeve rearward end 48.

In one example, the drive tool cavity 36 is substantially square andconfigured to mate with a ½ inch drive socket. It will be understood,however, that the drive tool cavity 36 can also be configured to matewith a drive socket of a different size and/or shape without departingfrom the scope of the present invention. Preferably, at least one of theinner surfaces of the drive tool cavity 36 can include a smalldepression for selective engagement with a drive socket securementdetent. The drive tool cavity 36 allows a drive socket to secure to theretaining knob tool 10 and significantly increases the level of torquethat can be applied to a pull stud 34 for tightening and removing a pullstud 34 from a tool holder 67.

A tubular end stop 54 may advantageously be affixed to the tubular bodyrearward end 16, where the tubular end stop 54 is sized to fit withinthe tubular sleeve 42 and has a circumferential edge 56 sized to strikeagainst a circumferential protruding edge in the tubular sleeve when thetubular body is moved into a release position as described in moredetail below.

Referring now to FIG. 2A, a planar cross-section of the tool of FIG. 1in a release position is schematically shown. In the release position,the retaining knob may be inserted or removed into the retaining knobtool 10. The plurality of balls 32 are each sized to individually fitinto one of the ball retainer sockets 30 and are moveable thereinbetween an inward lock position and a release position. In the releaseposition, the retaining knob may be inserted into or removed from theretaining knob tool 10. The sleeve forward end 46 includes a recessedcircumferential portion 50 encircling a first thicker portion of theinside wall 44. When the tubular body 12 is extended into the releaseposition, the plurality of balls 32 are driven outwardly by the knobportion 60 of the retention knob 34 into the recessed circumferentialportion 50.

Referring now to FIG. 2B, a planar cross-section of the tool of FIG. 1in an inward lock position is schematically shown. In the inward lockposition, the retaining knob may be inserted so that the knob portion 60protrudes rearwardly beyond the plurality of balls 32. The top plate 28is moved rearwardly to position the plurality of balls 32 within thefirst thicker portion 52 of the inside wall 44. The plurality of balls32 are held inwardly under the tapered bottom 70 of the retainer knobportion 60 so as to hold the retainer knob 34 in place. In one example,first thicker portion 52 may include a rearwardly angled edge 53 tofacilitate sliding the tubular body 12 into the tubular sleeve 42.

Referring now to FIG. 3, an example of a tubular body including aninternal bore used in the retaining knob tool is schematically shown. Aretention knob aperture 38 is recessed within the top plate 28. Theretention knob aperture 38 may preferably be a lateral slot openingsized and configured to laterally receive and position the retentionknob flange sections 64 and wrenching flats 68 in substantially thecenter of the top plate 28. In one example, the retention knob aperture38 is bounded by dual parallel inner walls 40 and opposing dual curvedend walls 41, where each of the opposing dual curved end walls 41 spansand adjoins one end of each of the dual parallel inner walls 40.Retention knob specifications are well known in the art and availablefrom commercial sources in the United States, for example.

Referring now to FIG. 4, an example of a stop for limiting longitudinaltravel of the tubular body is schematically shown. The stop 54 mayadvantageously be a second tubular body that is shorter than the tubularsleeve 42 and sized to fit within the tubular sleeve 42. A firstelongated portion 55 of the stop 54 is sized to frictionally fit withinthe inside tubular wall 44 where it may be affixed to the tubular body12 by attachment means known in the art. A second, smaller circumferenceportion 57 of the stop 54 extends forwardly into the inside tubular wall44 when inserted.

Referring now to FIG. 5, an example of a tubular sleeve as used in theretaining knob tool as seen from a sleeve rearward end is schematicallyshown. The tubular sleeve has an edge 56 protruding from the innertubular wall 44 within the sleeve rearward end 48. The edge 56 has awidth and diameter adapted to meet edge 59 formed between firstelongated portion 55 and the second, smaller circumference portion 57 ofthe stop 54.

Referring now to FIG. 6, an illustration of an assembled retaining knobtool in a retaining knob release position is schematically shown. Inoperation, when the tubular body is moved in the forward directionindicated by directional arrow 58 with respect to tubular sleeve 42, theretaining knob tool is placed in the release position. The tubular endstop 54 prevents travel of the tubular body 12 beyond the distance wherethe end stop 54 meets the tubular end stop circumferential edge 56. Insome examples, the retaining knob tool may be configured to be placed inthe release position or the engagement position by rotating theretaining knob tool to release or engage the retaining knob.

Referring now to FIG. 7, an example of an assembled retaining knob toolin a retaining knob inward lock position is schematically shown. Inoperation, when the tubular body is moved in the rearward direction sothat the top plate meets with the forward edge 49 of tubular sleeve 42with respect to tubular sleeve 42, the retaining knob tool is placed inthe inward lock position.

Having described the elements of the tool in detail, it is nowconsidered helpful to the understanding of the invention to explain itsoperation. In order to remove a retention knob from a CNC toolholder, anoperator would affix a socket wrench, for example, into the drive toolcavity 36. The retaining knob tool would be positioned into the releaseposition and inserted over the retaining knob to be removed. Once theretaining knob is fully inserted, the retaining knob tool can bepositioned in the inward lock position to hold the retaining knob andengage the retaining knob wrenching flats with the retention knobaperture walls. The retaining knob is now ready to be unscrewed from theCNC toolholder by turning the socket wrench in the, for example,counterclockwise direction.

The retaining knob tool can also be used to insert a retaining knob in aCNC toolholder by first inserting a loose retaining knob into theretaining knob holder and putting the retaining knob holder in an inwardlock position. Then using the socket wrench, as above, the retainingknob can be inserted into a CNC toolholder by turning the wrench in the,for example, clockwise direction.

The invention has been described herein in considerable detail in orderto comply with the Patent Statutes and to provide those skilled in theart with the information needed to apply the novel principles of thepresent invention, and to construct and use such exemplary andspecialized components as are required. However, it is to be understoodthat the invention may be carried out by specifically differentequipment, and devices, and that various modifications, both as to theequipment details and operating procedures, may be accomplished withoutdeparting from the true spirit and scope of the present invention.

What is claimed is:
 1. A tool for installation and removal of computer numerical control retention knobs comprising: a tubular sleeve with an inside tubular wall, a tubular sleeve forward end and a sleeve rearward end; a tubular body, slidingly held in the tubular sleeve, the tubular body being symmetrically formed around an axis and including a forward end and a tubular body rearward end, the tubular body having an internal bore bounded by an internal tubular wall surface and a rearward wall, and an external tubular body surface, the forward end being joined with a top plate having a larger diameter than the tubular body surface, at least two locking ball retainer sockets formed in the tubular body at the forward end below the top plate, the retainer sockets being substantially normal to the axis and located radially uniformly around the tubular body; a retention know knob aperture recessed within the top plate, wherein the top plate includes a top plate center; a plurality of balls, each ball being held in each of the two locking ball retainer sockets and being moveable therein; a tubular end stop affixed to the tubular body rearward end, the tubular end stop being inserted into the tubular sleeve, the tubular sleeve further including a protruding circumferential edge sized to strike against the tubular end stop when the tubular body is moved into a release position; a drive tool cavity, recessed within the tubular body rearward end, the drive tool cavity being sized and configured for receival of a drive tool; and the tubular sleeve forward end includes a recessed circumferential portion bounded by a first thicker portion of the inside tubular wall, the first thicker portion bearing against the plurality of balls forcing the plurality of balls inwardly when the tubular body is moved into an inward lock position and the inward force is removed from the plurality of balls when the tubular body is moved into a release position.
 2. The tool of claim 1 wherein the plurality of balls includes at least four balls; and the at least two locking ball retainer sockets include four locking ball retainer sockets; and each of the plurality of balls is individually inserted into one of the four locking ball retainer sockets.
 3. The tool of claim 1 wherein the drive tool cavity is sized and shaped to mate with a drive socket.
 4. The tool of claim 1 wherein the retention knob aperture comprises a lateral slot opening located substantially in the top plate center, the retention knob aperture being sized and configured to laterally receive and position retention knob flange sections and wrenching flats.
 5. The tool of claim 1 wherein the tubular end stop comprises a second tubular body that is shorter than the tubular sleeve and sized to fit within the tubular sleeve; a first elongated portion of the tubular end stop is sized to frictionally fit within the inside tubular wall where it may be affixed to the tubular body; and a second, smaller circumference portion of the tubular end stop extends forwardly into the inside tubular wall when inserted.
 6. A tool for installation and removal of CNC retention knobs comprising: a tubular sleeve within an inside tubular wall, a sleeve forward end and a sleeve rearward end; a tubular body, slidingly held in the tubular sleeve, the tubular body being symmetrically formed around an axis and including a forward end and a tubular body rearward end, the tubular body having an internal bore bounded by an internal tubular wall surface and a rearward wall, and an external tubular body surface, wherein the forward end is joined with a top plate having a center and a larger diameter than the tubular body surface, four locking ball retainer sockets formed in the tubular body at the forward end below the top plate, where the four locking ball retainer sockets are substantially normal to the axis located radially uniformly around the tubular body; a retention knob aperture recessed within the top plate, wherein the retention knob aperture comprises a lateral slot opening located substantially in the top plate center, the retention knob aperture being sized and configured to laterally receive and position retention knob flange sections and wrench flats; at least four balls, where each ball is individually held in a different one of the four locking ball retainer sockets and is moveable therein; a tubular end stop affixed to the tubular body rearward end, where the tubular end stop is inserted into the tubular sleeve, where the tubular sleeve further includes a protruding circumferential edge sized to strike against the tubular end stop when the tubular body is translated into a release position; a drive tool cavity, recessed within the tubular body rearward end, where the drive tool cavity is sized and configured for receival of a drive socket; and the sleeve forward end includes a recessed circumferential portion bounded by a first thicker portion of the inside tubular wall, where the first thicker portion bears-against the at least four balls forcing the at least four balls inwardly when the tubular body is translated rearwardly into an inward lock position and the inward force is removed from the at least four balls when the tubular body is extended forwardly into a release position.
 7. The tool of claim 6 wherein the tubular end stop comprises a second tubular body that is shorter than the tubular sleeve and sized to fit within the tubular sleeve; a first elongated portion of the tubular end stop is sized to frictionally fit with the inside tubular wall where it may be affixed to the tubular body; and a second, smaller circumference portion of the tubular end stop extends forwardly into the inside tubular wall when inserted. 